Síntese e caracterização de novos complexos de cobre(II) contendo ligantes naftalato-imina e aminopirazois de interesse medicinal

Abstract

The development of new drugs is a challenge due to the high cost and low success rate. Thus, N-heterocyclic compounds and Schiff bases are classes of ligands known to be effective as pathogens for bacteria and fungi. This property can be improved through the coordination of these ligands with the copper(II) ion. Cu(II) complexes have been extensively investigated in biological chemistry, showing antibacterial, antifungal, anticancer properties, among others. From this, seven organic compounds (called pre ligands) were synthesized. The in silico study evaluating the pharmacological potentials of the synthesized compounds was carried out. The pre-ligands were divided into two classes: naphthalate-imine (1a-1e) and aminopyrazoles (1f-1g). All ligands were characterized by nuclear magnetic resonance of 1H and {1H}13C, vibrational spectroscopy in the IR region, electron spectroscopy in the UV-Vis region and some of them elemental analysis of C, H, N (1a, 1b, 1d and 1e). The in silico study showed the pharmacological potential that these compounds have, and especially their excellent Caco-2 cell permeability, which is reliable for predicting the absorption of new drug candidate compounds orally. The theoretical oral absorption percentage of all compounds 1a-1g exhibited values above 90%. From the pro-ligands, eight copper(II) complexes were synthesized containing tridentate ligands of the z-naphthalate-imine type [z = N, O, S] (class 2a-2e) and bidentate ligands of the type (N,N ) aminopyrazoles (class 2f-2h). All complexes were characterized by vibrational spectroscopy in the infrared (IR) region and electron spectroscopy in the UV-Vis region. The complexes were also analyzed for their fluorescence property. Structural characterization was evaluated by density functional theory (DFT). The 2a-2h complexes showed fluorescent properties and the DFT study identifies the probable chemical structures of these Cu(II) complexes. The characterization of the electronic properties was performed by IR spectroscopy and spectroscopy in the UV-Vis region. Both techniques indicate the formation of the complex. In IV by changing the wave number referring to C=N. In UV-Vis by the change in the wavelength of the electronic transitions, in addition to the presence of d-d bands.